Authorities are looking for a Florida quadruple amputee in connection with the murder of his parents.

Sean Petrozzino, 30, is on the run and considered armed and dangerous, authorities say. He went missing after his parents were found fatally shot in their home, and he is believed to be driving his father’s red Toyota Camry.

Petrozzino has two prosthetic legs and no hands. He became an inspiration in his community as a teenager when he kept smiling after losing his limbs to bacterial meningitis.

At the time, the South Florida Sun Sentinel called him perky, silly and polite.

Back in 2000, he told the paper, “Lots of important things in my life just happened by chance. You know someone and get a job that makes you millions of dollars, or you get a disease. There doesn’t seem to be any reason some things happen.”

Authorities say Petrozzino had moved back in with his parents a week before the murder after separating from his wife.

Authorities searching for Petrozzino note that he should be easy to spot… and yet, they’ve been unable to find him so far.

We share this story for one reason, and one reason only: never assume that someone you run across is incapable of being a threat. The mind and the will of an individual is what matters. Everything else—including body parts—are just tools to be used as the mind dictates.